I have an unusual question type, where I need to use a side-by-side to present what is essentially a bi-polar matrix question, except that I have pre-tested multiple versions of a bi-polar matrix (and bi-polar sliders, and various other options) and everyone comes back to saying the below side-by-side format is the easiest to comprehend, and all answered it as desired except for 2 people who ran into a limitation of the format.
The issue is that if you select an option in one column (eg. Single-use) and then change your mind and want to select an option in the other column (eg. Reusable) there is currently no way to DE-SELECT your answer in the first column, as you can't de-select single-choice options, so you end up with two selections, which makes your response void.
Unfortunately, the standard de-select workaround (to make multiple choice and then make all answers exclusive) does not work in side-by-side ('make exclusive' is not available to scale points in side-by-side).
I therefore need something that will either evaluate the number of response in a row across BOTH columns and set that to max 1 (so that whenever you try to select a 2nd choice it deselects your 1st choice) -- preferred; OR something that allows you to deselect any choice by clicking on it again.
(Alternatively, a third solution would be code that allows floating labels added via javascript to have display logic attached to them - please see below, about my second-best option.)


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For interest's sake, the other option that came close to working was a bi-polar scale, which used javascript to float the right-hand side labels. However I can't find a way to add display logic to the floating labels, which means that if logic prevents a particular row from showing, Qualtrics still displayed the floating label, in the next available row, so you couldn't tell what the correct label was.
Back-end of slider:
JS code to make floating right labels:

Front-end of slider - when all options selected:

Front-end of slider when first option (baking paper/foil) not selected - labels are now out of sync:

The same thing happens with bipolar matrix labels, and I also tried about 4 different ways of labelling a matrix to get the same effect as a side-by-side, similar to the below examples, but the weird spacing of the labels (even when I tried to adjust) just didn't work, and even when I floated 'Single-use' and 'Reusbale' over the top of 'Most of the time' middle options, the lack of a line between the two halves was still reported as being a problem in understanding the two ends of the scale.